Mammalia, Carnivora, Ursidae
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e390-11 De Bonis.qxd 30/1/12 14:15 Página 179 Estudios Geológicos, 67(2) julio-diciembre 2011, 179-186 ISSN: 0367-0449 doi:10.3989/egeol.40553.181 A new species of Adelpharctos (Mammalia, Carnivora, Ursidae) from the late Oligocene of the “Phosphorites du Quercy” (France) Una nueva especie de Adelpharctos (Mammalia, Carnivora, Ursidae) del Oligoceno Superior de las “Fosforitas de Quercy” (Francia) L. de Bonis1 ABSTRACT The genus Adelpharctos was known until now through the species A. mirus by a unique mandible (p2-m2) from the old collections of the Quercy whose geological age was unknown. New material com- ing from the locality of Pech-du-Fraysse completes our knowledge of the genus particularly for the maxil- la and upper teeth. Adelpharctos belongs to the sub-family Hemicyoninae in the family Ursidae. It differs from the middle Miocene hemicyonines which have more massive molars and from the group Cephalo- gale-Phoberogale by some morphological characters. It seems to be a branch coming from the ancestral stem group of the sub-family. Keywords: Late Oligocene, France, Quercy, Carnivora, Ursidae, Hemicyoninae. RESUMEN El género Adelpharctos era solo conocido por una especie A. mirus representada por una única mandibular (p2-m2) procedente de las colecciones antiguas del Quercy, cuya edad geológica es des- conocida. Nuevo material procedente de la localidad de Pech-du-Fraysse completa nuestro conoci- miento sobre el género, en particular para el maxilar y la dentición superior. Adelpharctos pertenece a la subfamilia Hemicyoninae, familia Ursidae. El género difiere de los hemicioninos del Mioceno medio, que tienen dentición más robusta, y de los del grupo Cephalogae-Phoberogale por algunos caracteres morfológicos. Se interpreta como perteneciente a una línea procedente del grupo ancestral primitivo de la subfamilia Hemicyoninae. Palabras clave: Oligoceno superior, Francia, Quercy, Carnivora, Ursidae, Hemicyonidae. Introduction museums through the whole world. The sediments and the fossils were provided by many quarries dis- Although they were used from the last third of persed over a large surface of hundreds of km2. the 19th century to the beginning of the 20th to Several palaeontological studies of different mam- extract phosphate used as fertilizer for agricultural mals (Gervais 1872 a & b; Filhol 1872 a & b, 1874, needs, the fissure, cave and chasm fillings of the 1876, 1877, 1880, 1882; Gaillard 1908; Schlosser “Phosphorites du Quercy” are essentially well 1888, 1889, 1891) leaded to the conclusion that the known because the myriads of fossils which were deposits may represent a large range of time from mixed with the sediments. Among these fossils, the late Eocene to late Oligocene but that, except in thousands of vertebrate bones, particularly mammal rare cases, the fossils were mixed in every locality. bones, were unearthed and stored in number of Other studies especially focused on Carnivora of 1 IPHEP, UMR 6046 du CNRS, UFR Sciences, Université de Poitiers, 40 Avenue du recteur Pineau, 86022 Poitiers, France. Email: [email protected] e390-11 De Bonis.qxd 30/1/12 14:15 Página 180 180 L. de Bonis the old collections (Teilhard 1915; Piveteau 1931, Material and methods 1942/1943, 1962; Bonis 1966, 1971, 1981; Gins- burg 1966, 1979; Lange-Badré 1969, 1970; Peigné The studied material comes from the locality of Pech-du- 2000, 2001, 2003; Peigné & Bonis 1999; Wolsan & Fraysse (Saint Projet, Tarn-et-Garonne, France) in the military camp of Caylus (Crochet 1971). It comprises a right hemi- Lange-Badré 1996) could not clear the problem of mandible with the alveolus of i3 and c, p1, broken p2, p3-m2, the fossil dating as well. In fact, the names some- alveolus of m3 and a right maxilla with an alveolus of P1 and times labelled on the fossils (Mouillac, Lamandine, P2-M2. The two specimens have been found close together Saint Antonin, Prajoux, Mémerlin…) correspond to with a similar wear pattern and they clearly belong to the same quite large areas containing many fillings whose individual. The fauna contains many species of small and large vertebrates which allow a precise biochronological dating and geological ages may be very different. Thus the thus the locality is the reference biochronological level MP 28 material of the old collections which was listed in a (see Remy et al. Biochrom 97 p. 792-793) about 25-26 Ma old. catalogue (Sigé et al. 1979) was a taxonomic melt- The order Carnivora is well represented in the old collections ing pot without any indication of the chronology as well as in the new ones (Bonis 1974, 1976, 1978; Bonis & despite some very complete and nice specimens. Cirot 1995; Cirot & Bonis 1992, 1993; Peigné & Bonis 1999, 2003) and the genus Adelpharctos as well as the type-species A. Moreover, many people thank that the works were mirus were described from a well preserved but unique stopped in the Quercy because all the fissures were mandible of the old collections (Bonis 1971). The new material empty without any phosphorite or fossil. completes our knowledge on the anatomy and biostratigraphic Nevertheless, a new phase of researches began position of this genus. The measurements were taken with an before the second world war, when Gèze (1938 a, electronic calliper to 1/100° and given to 1/10°. 1938 b) demonstrated that each of two fissure fill- ings quite close contained a homogeneous fauna. During the second half of the sixties, a scientific Systematics team coming from the universities of Montpellier II (USTL), Paris 6 (UPMC), Lyon 1 (Claude Order Carnivora Bodwich, 1821 Family Ursidae Fischer de Waldheim, 1817 Bernard), the Muséum national d’Histoire naturelle Sub-family Hemicyoninae Frick, 1926 Paris and later the University of Poitiers carried out Genus: Adelpharctos Bonis, 1971 several field campaigns in the Quercy which gave Type species: Adelpharctos mirus Bonis, 1971 rise to a large number of general publications on the Other species: A. ginsburgi n.sp. Quercy phosphorites faunas (Bonis et al. 1973; Bonis et al. 1974; Bonis et al. 1977; Crochet et al. Emended diagnosis: Dental formula: 3/3 I, 1/1 C, 4/4 P, 2/3 M. Hemicyoninae with a more cutting dentition than the other 1975; Crochet et al. 1981; Hartenberger et al. 1974; genera of the sub-family, m1 shorter relative to the premolar Gèze et al. 1978; Remy et al. 1987) and many other row with a less reduced metaconid and a talonid tapering back- ones showed that every fissure had an original ward. P2-3 with three roots, P4 short and robust, triangular fauna and of which two of them may precise the shaped M1 with a metaconule more buccal than the protocone, a hypometacrista joining the base of the metacone and with a global geological age of the Phosphorites du Quer- modest linguo-distal cingulum. cy which are now dated from the middle Eocene (Astruc et al. 2000) to the early Miocene (Sigé et Adelpharctos ginsburgi n. sp. al. 1991). In every site, the fossiliferous levels are Holotype: right mandible with alveolus of i3, c-m2, alveolus quite shallow and deposited during a relatively of m3 and right maxilla with alveolus of C-P1 and P2-M2 short time. The amount of variation in every species (PFRA 34). Locality: Pech-du-Fraysse, Lot (France) is similar to that of extant species (Vianey-Liaud & Dating: Late Oligocene (MP 28) Legendre 1986). Because the large number of sites Origin of the name: dedicated to my colleague the late and the possibilities of evolutionary studies, the Léonard Ginsburg for his numerous works on the carnivorans. Quercy phosphorites constitute a true open air labo- Diagnosis: Adelpharctos smaller than the type-species A. ratory of vertebrate evolution (Bonis et al. 1977). mirus, p4 slightly less robust with a minute posterior accessory cuspid, metaconid of m1 slightly less posterior, talonid basin of There are several fossil bearing localities which m1 slightly less reduced. are used as level markers in the frame of the conti- nental Paleogene biochronology establishing a scale founded on the evolution of mammalian faunas as Description are the American “Ages of mammals”. Some of the mammalian level markers are Quercy phosphorites Mandible (Fig. 1-2; Table 2): The ramus is complete except localities (see Biochrom 1997). a small portion of the coronoid process. The corpus mandibu- Estudios Geológicos, 67(2), 179-186, julio-diciembre 2011. ISSN: 0367-0449. doi:10.3989/egeol.40553.181 e390-11 De Bonis.qxd 30/1/12 14:15 Página 181 A new species of Adelpharctos (Mammalia, Carnivora, Ursidae) 181 Table 1.—l = length; w = width; trL = trigonid length; trw = trigonid width; talw = talonid width Lower teeth cL cw p1L p1w p2L p2w p3L p3w p4L p4w m1L m1trL m1trw m1talw m2L m2trw m2talw A. mirus 9,9 4,6 12,3 6,8 19,3 14,2 8 7,7 10,8 7,2 6,3 A. ginsburgi 9,3 6,1 5,7 3,9 9,8 3,7 10,5 5,4 17,2 12,7 7,5 7,3 9,9 6,5 5,4 Fig. 1.—Adelpharctos ginsburgi n. sp. Right mandible (PFRA 35); A: buccal view, B: lingual view (Scale bar = 3 cm). lae is slightly elongate with a quite short symphysis; there are two small mental foramina, one anterior and situated beneath the mesial root of p2, another one posterior beneath the mesial root of p3, both at midheight of the ramus. In the lingual sur- face, the foramen mandibulare is relatively small and opens 21 mm in front of the condyle. The ventral border is slightly con- vex under the tooth raw, the deeper part being under m2, and it turns upward under the coronoid process. The latter is high with a deep masseteric fossa limited downward by a rough crest and extending to the alveolus of m3.